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Aug. 4, 2011 -- They say the eyes are the mirrors to the soul, but it’s our nails that may provide a snapshot of our health.

Taking care of our fingernails and toenails and knowing when to see a dermatologist can go a long way toward making sure our nails look great and protecting our health, according to dermatologists speaking at the American Academy of Dermatology summer meeting in New York City.

“Nails are an indicator of internal health,” says Zoe Draelos, MD, a dermatologist at Duke University School of Medicine in Durham, N.C.

Protecting your nails -- and your health -- starts with:

Bringing Your Own Tools to Your Nail Salon

This is the best thing you can do for your nail health, Draelos says. “Using your own tools can help reduce your risk of developing fungal infection from shared instruments that aren’t properly sterilized.” These infections are showing up in younger and younger salon patrons because adolescent girls are having birthday parties in nail salons. “Nail parties are here to stay, and we are seeing nail fungus in young girls,” she says.

To help combat fungal infections, many salons are offering clients antifungal liquids or gels, and that is all well and good, she says. But “make sure your dermatologist knows if your salon uses one of these products as they can interfere with skin cultures done on your nails,” she says.

Choosing Nail Shellac Instead of Nail Polish

Got brittle nails? Consider shellac instead of traditional nail polish, Draelos says.Nail shellac “is not a polish and uses the same type of material that is used in dental sealants.” It can last up to six weeks, "doesn’t chip, smudge, and you can’t scrape it off with a key,” she says. “Nail shellac can be pigmented with colors of the rainbow, and glitter and foil confetti can also be added. It helps prevent brittle nails by reinforcing the nail and improves hydration to the nail.”

For these reasons, “shellac is quickly replacing polish in professional nail salons.” It is applied in three coats, and in between each coat, you must place your nails under a ultraviolet (UV) light dryer. This UV light may pose some risks to the eye, so wearing protective glasses may benefit manicure junkies, Draelos says.

Taking Biotin Supplements

Phoebe Rich, MD, director of the nail clinic in the department of dermatology at Oregon Health & Science University in Portland, recommends taking 2.5 milligrams of biotin, a B vitamin supplement, a day to help strengthen your nails.

Wearing Gloves

“Use gloves for wet work, gardening, and chores,” Rich says. This can protect nails from breaking as water softens your nails, especially when combined with heavy-duty scrubbing.

Telling the Manicurist What Not to Do

“Don't let them buff or sand the surface of your nail before polishing because this thins or weakens the bed,” Rich says.

Also, “don’t let them push back your cuticles,” says Michele Green, MD, a dermatologist at Lenox Hill Hospital in New York. “If you don't push back cuticles there is no portal of entry for fungus. It’s that simple.”

Knowing What to Look Out For

“A dark line or mole under a finger- or toenail could be melanoma,” Green says. “Lines, rippling, and pitting of the nail may be a symptom of the skin condition psoriasis or another inflammatory disease.” Blueness in the nail can be a sign of lung infection, diabetes, or another circulatory problem, she says. “Splitting, yellow, and brittle nails can be signs of anything from fungal infection to thyroid disease, and nails that are white toward the bed with a darker circle surrounding the whiteness may indicate liver disease. If something doesn’t look right, see a dermatologist.”